Metal-clad electric switch gear of the draw-out type



v I v March 15, 1927. w ANDERSON ET AL 20,792

METAL GLAD ELECTRIC SWITCH GEAR UP THE DRAW-OUT TYPE 7 Filed 1926 4 Sheets-Sheet 1 k J W 4%,, IIII bllll: 501.

1,620,792 March 1927' w. ANDERSON ET AL METAL GLAD ELECTRIC SWITCH GEAR OF THE DRAW-OUT TYPE Filed Feb. 4, 1926 4 Sheets-Sheet 2 March 159 1927' ANDERSON ET AL METAL CL-AD ELECTRIC SWITCH GEAR OF THE DRAW0UT TYPE I Filed Feb. 4, 1926 4 Sheets-Sheet 5 March 15, 1927.

1,620,792 W. ANDERSON ET AL METAL GLAD ELECTRIC SWITCH GEAR OF THE DRAW-OUT TYPE Filed Feb. 1926 4 Sheets-Sheet 4 Patented Mar. 15, 1927.

rtJ'NiT E'D? STAT as PAT Eur ser-es.

W'ILLIAM ANDERSQN, orrnnneunnbn-rfzrin; AND HENRY wrL IAIu cno'rnrnn, or

wALL-sEnn-on-rYnn,ENGLAND; ASSIGHORS ro'a. REYRoLLE a coarser-TY LIM- rrnn, or nr'sn'oan-on-rvnn; nnernnn a-cotrrnny or GREAT BRITATN.

METAL-GLAD ELECTRIC SXVI'ECH GEAR-OF THE DRAXV-OUT TYPE.

Applicationfiled February 4, 1926, Serial No. 86,103. and inGreat Britain April 2, 1925.

This invention relates to metal-clad electric switchgear oi the draw-out type and lore particularly to switchgear in which the sockets on the fixed portion of the gear are provided with doors or covers which are opened and closed automatically by the movementot the draw-out portioniot' the gear. These doors are hinged or pivo'led and when the drawrout-portion of the gear is racked in they are caused by theaction of operating rods to told together and slide into a space-between two sockets-tor instance a busbar socket and a transtor .161 socket, i

provision b-eingmade-for aiurther racking in motion of the draw-out portion without turthermofion of the doors.

T he ob ects of the present invention are an improved construction and arrangement of the operating gear for these doors or coversto the operatirn rod so that when the door is opened by the racking in of the movable portion 01"" the gear the turning of the door about its hinge or pivot'trees the operating rod from its positive engagement with the draweout portion and allows that portion tocontinue its racking in motion.

This operative counecvion between the door and the operating rod 18 conveniently made by means of bevel gear, abevel pinion mounted on the lungs or pivot of'the door en 'a 'in with another bevel inion on the l D C3 C3 operating rod. The operating rod has its ends supported in sleeves orguideson the fixed and draw-out portions respectively, the sleeve or guide on the draw-out portion having a longitudinal slot with a; transverse notchor recess in it and the adjacent end of the operating rod being furnished with a pin or grub screw which by rotation ofthe rod can be brought out of, the longitudinal slot into the transverse recess or vice versa. It is this partial rotation of the rodwhich' is effected bythe opening and closing of the door through the bevel or other gear above mentioned. 7 v

In switchgear otthe type to whichthis inbeing the lower socket of the two or more sockets-on the gear. To do this an extension plug is placed in the corresponding socket oi ,the draw-out portion and afternthe door or coverot the transformer socket has been opened the draw-out portion: is racked in suiiiciently' tobring the plug into engagementwith the socke appropriate earthing iconnecions having been made on the drawout portion. It is very desirable that when carrying out this operation which necessitates the opening of the transformer socket door by hand that there should be no risk of the busbar chamber socket door being opened by mistake. To obviate this risk according to this invention the door of the busbar chamber is so arranged that whilst it can be opened and closed through. the action of the operating rod in the normal use of the gear, it cannot be opened by hand from its closed position. This arrangement conveniently takes the form of acurveo catch cooperating with a slot in the door and so shaped that it allows the door to open when its hinge or pivot is being shifted by the movement of the operating rod but prevents the turning of the door about its hinge or pivot when that member is stationary.

In multi-phase switchgear the doors of -neighl'iouringphase sockets are usually con nected by a web or plat-e and this web can be slotted to allow a fixed curved plate catch to pass ,through it the dimensions of the slot and the curve of the catch being such as to fulfil the conditions above mentioned.

' Vhen the invention is applied to switchgear having duplicate busbar sockets one above the other, each of the busbar socket doors is furnished with a catch or other looking arrangement acting in the manner described and in such a case the operating rod for the upper. busbar socket merely slides'in guides on the fixed and draw-rout portions respectively and is connected by a tie to the operating rod for the doors of the lower busbar chamber and the transformer chamber. This lower rod,- as previously mentioned, is provided with pins and the slotted and notched guide and is geared through the T bevel pinions to the door of the transformer socket; I

The sleeves or guides on the draw-outper- I some deliberate action.

Springs may be provided to counteract any tendency of the pins or grub screws from sticking 1n the longitudinal {slots in the gtudes. V

In the accomoan m ClIRWID S which 11- 1 a 2: lustrate by way of example one construction of the invention as applied to draw-out switchgear for duplex busbars,

F i 'ure 1 1s a side elevation with a detail in section showing the draw-out portion in .of tne fixed portion of the near.

its withdrawn position andthe doors closed,

Figure 2 is a section on the line 22 of n1gure 1 showing the closed doors in elevation,

Figure 3 is a view drawn to a larger scale of" a portion of Figure 2 with a part in section, 7

Figure 4 is a part section on the line 44 of Figure 2 drawn to the same scale as Figure 3 but showing the doors A B in the act of being opened, 7

Figure 5 is a view similar to Figure 1 7 but showingthe draw-outportion racked in and the doors open,

Figure 6 is a view similar to Figure 1 but showing the door of the transformer chamber open, and

Figures 7 and 8 are detail views of the guide tubes on the draw-out portion of the gear to show the interconnection between the rods, the tubes and the retainin studs, Figure 7 showing the positions of the parts when the draw-out portion is racked outand Figure 8 the positions when it is racked in.

Like letters indicate like parts throughout the drawings. I

In these drawings A and A are the busbar sockets or chambers and B the transformer socket or chamber, all forming part- C and C are the plugs for the busbar sockets A and A respectively and D is the plug for the transformer socket B, these plugs all being carried'on the draw-out portion of the gear. The switchgear shown is designed for use on a three-phase system so that there are three sets of plug and socket connections arranged side by side in the usual manner.

All the chambers or sockets are provided with doors marked A A and B respectively and the doors in each horizontal row are connected by webs as maybe seen by reference to Figure 2. r

The operation of opening and closing the doors is brought about by the backward and forward movementof rods E and E mount ed in guides F on the fixed portion and guide tubes G and G on the draw-out portion.

The lowest or transformer chamber door B on each side is secured say by a pin, to a tube E (Figure 3) which can turn about a rod H and carries a bevel pinion H pinned to the tube and engaging with a similar pinion H on the rod E which passes through and can rotate in an eye H on the rod H *011 each side of this eye H is a collar E pinned to the rod E.

The lower busbar chamber door A is hinged about the tube H, that is to say it can turn on the tube and is not pinned to it. The upper busbar chamber door A at each side of the gear is similarly hinged about a rod H carried between collars E on the rod E Springs J are provided which tend to keep all the doors closed over the mouths of their respective chambers.

The end of the rod it remote from the fixed portion of the gear slides in the guide tube G which is formed with a longitudinal slot G and; a transverse slot or notch G It is also formed with a second transverse slot or notch G whose function is described later.v

When the draw-out portion is in the racked out position, i. e. that shown in Fig ure 1, a pin or grub screw 11, on the rod E is in engagement with the transverse slot G and therefore, if the draw-out portion be.

racked in, the rods E will be pushed forward and by means of the collars E will carry the rods or pivot pins H backwards thus causing the doors A and B to open, as shown in full lines in Figure 4, against the action of the springs J. The rods E are merely guided bv their tubes G which are not provided with the slot and notches of the tubes G, but the rods E are tied to the rods E by the brackets or ties E so that the rods E also move with the rods E and the upper doors A are also carried back and opened.

As the transformer chamber door B is opened the tube H to which it is pinned is partially rotated and consequently the bevel pinion H turns and through the pinion H rotates the rod E. This causes the grub screw or pin E to move in the transverse slot G until it is finally brought out of that slot into the longitudinal slot G By this time the doors are fully open and are folded andv stowed between the chambers as indicated in Figure 5. Further racking in movement of the draw-out portion to complete the' lue' and socket connections is now possible without moving the rods E, for the tubes Gnow slide forward on the rods. The pin E being in the longitudinal slot Gr permits of this movement. This final closed position of the gear The reverse operation takes place when racking out the draw-out portion, the guide tubes G first sliding over the rods E and consequently not moving the doors until the grub screws or pins E are at the inner end of the longitudinal slots G the transverse notches G Furtheroutward movement pulls the rods .E and E and brings the rods or pivot pins H and H forward so that the doors may turn under the action oftheir springs into their closed positions. In thus moving the lower door B operates the bevel gear and the rod E is rotated, this movement being allowed by the transverse slot or notch G lVhen, as is sometimes necessary, the lower 'or transformer socket B has to be earthed through theracking in of the draw-out portion after some part of that has been connected to earth, this can be done by opening the door B by hand and holding it open as for example by a link as at K in Figure 6. This movement of the door B turns the rods E wand brings'the grub screwsnor pins E out. of the transverse notches G into the longitudinal slots G The drawout portion can then be racked in without operating the doors and it' an extension plug or earthing contact such as L be placed on the plug D, this racking in motion will suthce to earth the socket- B whilst the busbar chamber doors A .and'A remain closed.

Whilst it is desirable thus to be ablev to open the transformer chamber doors B by hand, it is important that there should be no risk of one of the busbar chamber doors A? and. 1A being opened by mistake and therefore provision is made to prevent this. In the construction illustrated the webs joining the busbar chamber doors are provided with slots M which in the normal opening. and closing movements of those doors pass freely over fixed curved catches N. The shape of these catches is such that they only allow the slots M to pass over them when the centres. i. e. the rods H and H about which the doors r 2 and A turn, are being moved by the normal operation of the switchgear, i. e. by the racking in or out of the draw-out portion. If it be attempted to open the doors A or A by hand, i. e. to turn them about the rods I 1 and H when those members are stationary, the catches N will foul the slots M and prevent the doors from being opened. This can be seen by reference to Figure 4 where one of the doors A is shown in chain lines in its closed position. It it be turned about its pivot rod H when in this position the edge of the slot M will obviously foul the fixed catch N whereas it the pivot rod H is being moved by the rod E in the normal operation of the gear the are described by the slot M corresponds to the curve of the catch N.

is shown in Figure 5.

and adjacent to i has been withdrawn and be slid over the rod portions by the tubes G and G and the rods E and E Whilst it is desirable that this may be done quickly and easily when the draw-out portion is withdrawn and the doors closed, it should be impossible to do it otherwise than with deliberate intent when the doors are open. For these reasons the tubes Gare made with the second transverse notch G previously mentioned andare secured in their supports on the draw-out portion of the gear in the way now to be described with refe'ence to Figure l and to Figures 7 and 8. As will be seen reference to Figure l the tube is secured to its support by two set screws. ()ne ot' these 0 has a milled head and thus can beread-ily and quickly removed. The other P has a head which necessitates the use of a spanner or tool and cannot be undone by hand. The stud {l grips the tube G whilst the stud P does not grip it but normally enters the second transverse slot Gr" and prevents any longitudinal motion of the tube relative to its support G When the (llflW-Ollt portion the doors are closed, the parts occupythe position shown in Figure l and Figure 7, i. e. the pin E is in the transverse slot G in a position corresponding to that ot'the stud P in the other transverse slot G Thus byloosening the one stud O thetubeG can beturned in its support in the direction 01" the arrow (Figure '4') which will bring the longitudinal slot into line with the pin E and the stud P, i. e. will disengage those members from their transverse slots. The tube G can then and freed from its support But when the doors are open, i. e. when the draw-out portion has been racked in, the position of tie parts will be as indicated in Figure 8 and then the mere loosening of the stud G will not be suificient, for as the pin E is now in the longitudinal slot the tube cannot be turned relatively to its support to bring the second transverse slot out of engagement with the stud P, neither can the tube slide longitudinally because of the presence of the stud P in its transverse slot. Consequently the stud P must be removed by a tool or spanner before the tube can be removed from its engagement with the draw-out portion. The two studs 0 and P are shown opposite to each other in Figure 1 but in Figures 7 and 8 the position of the stud P is slightly altered to make the above described action clearer. As previously mentioned the tubes G for the upper rods E are only guide tubes and they are therefore merely held by studs 0 funct oning similarly to the studs 0.

according to this invention not intended for -a duplex busbar system,

the upper busbar chambers A and doors A would not be present and the rods E and ties E would be omitted.

hat we claim as our invention and desire to secure by Letters Patent is z- 1. In electric switchgear of the draw-out.

type having sockets on the fixed portion provided with doors which are opened and closed by the reciprocation of operating rods attached to the draw-out portion, the combination with one of said doors of gear between it and its operating rod, such gear being actuated by the door itself when'it is opened to free the operating rod from positive engagement with the draw-out portion.

2. In electric switchgear of the draw-out type the combination of a fixed portion, socket chambers forming part of said fixed portion, hinged doors to said chambers, a drawout portion, an operating rod having one end held in a tubular support on said drawout portion and its other end slidably mounted on said fixed portion, and bevel gear between one of said doors and said operating rod acting to turn the rod and free it from its positive engagement with its tubular support on the draw-out portion when said door is opened.

3. In electric switchgear of the draw-out type the combination of a fixed portion, a. busbar socket chamber and a transformer socket chamber forming part of said fixed portion, hinged doors to said chambers, a draw-out portion, an operating rod having one end held in a tubular support on said draw-out portion and its other end slidably mounted on said fixed portion, bevel gear between said transformer chamber door and said operating rod acting to turn the rod and free it from its positive engagement with its tubular support on the draw-out portion when said door is opened, and means for automatically locking the busbar chamber door so that it cannot be opened by hand when in the closed position into Which it is moved by the withdrawal of the drawout portion of the gear.

4. In electric switchgear having the combination of parts set forth in claim 8 the combination with the busbar chamber door of a curved catch so shaped as to allow a slot to pass over it when the door opens under the action of the operating rod butto prevent the opening of said door by hand when said rod is inoperative.

5. Electric switchgear having the combination of parts set forth in claim 2 in which the operating rod is provided with a pin and is engaged with the draw-out portion by a tube having longitudinal and transverse slots to accommodate said pin, said tube being removably held in a support on the draw-out portion in such a manner that whilst it can be readily detached therefrom "hen the draw-out portion is racked out and the doors closed, such detachment can only be effected when the draw-out portion is racked in and the doors open, by the deliberate manipulation of two fastening members.

In testimony whereof we have signed our names to this specification.

WILLIAM ANDERSON. HENRY WILLIAM CLOTHIER. 

